The present invention relates to an automatic analyzer for clinical analysis and more particularly, is directed to an automatic analyzer which performs its own calibration in accordance with a standardized protocol used for correction of differences in measured data between the automatic analyzers of different facilities.
In clinical analysis fields, in recent years, it has been demanded to correct differences in measured data between automatic analyzers of different facilities, that is, standardize measured data. To this end, different standardized protocols are prescribed for different objects to be measured such as electrolyte, cholesterol and enzyme number.
Explanation will be made, in particular, in connection with the enzyme number. First, differences in measured data between the automatic analyzers result partly from the accuracies of the individual automatic analyzers. For the purpose of calibrating the automatic analyzers, standardized protocols have been prescribed (refer to "Standardized Protocol Manual", Japanese Association of Medical Technologists, compiled by Research Group of Clinical Chemistry, pp. 35-51, 1992).
According to the Standardized Protocol Manual, reaction product (which will be referred to as reaction inducing substance, hereinafter) for each enzyme such as Nicotinamide Adenine Dinucleotide Phosphate reduced-form (NADH) for Aspartate Aminotransferase and 4-Nitrophenol for amylase is directly or indirectly (actually, glucose is used for NADH) weighted, and the calibration is carried out manually by using the weighted reaction product as a standard solution.
JP-B-57-29996 discloses an enzyme analysis method for calculating an amount of enzyme in a test enzyme solution. In this enzyme analysis method, a device constant or K factor of each automatic analyzer is calculated and the amount of enzyme in the test sample solution is calculated on the basis of the device constant and the absorbance of the test enzyme solution.